Might be the case, hot Singapore tired battery, mine here in Canada go forever, oldest off brand I have is winter of 2003, it has less capacity but still half I'd guess.
i would be very interested to have a link to one of these companies, because the AAs i'm using in a 5D2 grip are getting drained faster than i would like, and i have yet to find a product that mimics the OEM batt function-for-function.
It was a UK company called "Digital Rev" that was marketing LP-E6 clones on eBay. They advertised:
Full compatibility LP-E6 Battery for Canon EOS 5D II. This battery has built-in SN chip, and is fully compatible with EOS 5D II battery information standard. This Battery does NOT require those 3rd party chargers to work. Simply use your own Canon original charger. Works just like original batteries.
They don't have an auction live right now for them, but this was the old auction address:
Hmm, I've never had a 511 actually last more than 2 years. Most die or have highly reduced capacity sometime after a year or so. And they only get charged a couple times a month.
You can expect a Li-Ion to fall below acceptable rechargeability levels between 24 and 36 months after manufacture even with the best of care.
Early death is most often attributed to keeping them warm in use or during charging (which is the real reason why those laptop "coolers" are useful).
Charging them to full capacity is also a factor in a shortened life. If you know you're not going to need every last erg of energy from a battery for a session, it's better to remove it from the charger as soon as the light stops blinking. If weeks are going to pass before you use it, charge it again just before that use.
Some laptops can actually be set to stop charging at less than 100% and not to recharge until the battery drops below another percentage that can be set (like 30%).
Here is the best information about maintaining Li-Ion (and other rechargeable battery types) on the Internet:
www.batteryuniversity.com
Isador Buchmann is president of Cadex, Corp, a Canadian manufacturer of rechargeable battery analyzers and chargers. He knows his stuff, he's not prejudiced about battery types or brands, he has real-world experience with all of them and has his own data, and he writes lucidly for laymen.
I use the Duracell hybrids (kinda like Eneloops), these cells are made in Japan, bought them from Walmart $12 for a pack of 4, I tried them in my grip last week and got about 620 shots out of them....MUCH better than I had expected, 5D2 is very energy efficient so I wouldn't hesitate to use these Duracell hybrids AA.
I shot 170+ shots today with a set of Eneloop, the battery display is still full. I think they are at least usable, and much cheaper than LP-E6, but heavier.
